@Ceilidhann I went maybe 10 years ago. I remember that the old town/old portion of the city was a lot of fun to walk around. I also enjoyed the modern art museum - it had a much more Russian/Soviet focus than what I was used to as an American.
@maureenjohnson It absolutely will be fine. You’ll have to pay some penalties, but that’s it. I’m an accountant and I actually have some clients who don’t pay estimates on principle - they think whatever they can do with their money instead of giving it to the IRS early is worth the penalties.